Few executives are more outspoken about the threat that distributed energy poses to utilities than NRG Energy CEO David Crane, so it’s not surprising that NRG Energy plans to sell a product that is disruptive to the centralized power business model.

The company is working with Deka Research on an on-site “energy appliance,” according to NRG Energy’s corporate sustainability report. In an interview last week with The Atlantic, Crane said the device, called Beacon 10, can generate electricity from natural gas, work with a battery and rooftop solar, and provide backup in the case of a grid outage. “When there’s not enough solar, you turn on the Beacon 10. Then, ideally, the grid itself would just be the ultimate backup. It’s the coolest thing I’ve ever seen,” he said.

Deka Research is headed by Dean Kamen, a renowned inventor best known for creating the Segway transporter who has worked extensively with Stirling engines. Earlier this year at the Fortune Brainstorm Green conference, NRG Energy showed a portable Stirling engine, and Crane said that the company is working with Kamen to test 200 of the machines in homes. Kamen has already made a multi-fuel, Stirling-engine-based water purifier called the Slingshot, which Coca-Cola will distribute to rural Latin America and African villages.

A specification sheet seen by the website Energy Choice Matters indicated that the Stirling engine of Beacon 10 is capable of producing 15 kilowatts of power, can send excess energy to the grid, and is slightly larger than a washing machine. The NRGBeacon10.com website has apparently since been taken down, and an NRG representative declined to provide more details on Beacon 10.

Beacon 10 is one of a number of products NRG Energy has that are outside the typical offerings of conventional utilities. The company has developed a solar canopy and has installed EV charging stations at retail locations. It’s also one of the utilities working with Nest Labs to offer consumers a two-way thermostat.